Congenital and Developmental Deformities of the Spine in Children With Myelomeningocele Abstract The treatment of spinal deformities in children with myelomenin- gocele poses a formidable task. Multiple medical comorbidities, such as insensate skin and chronic urinary tract infection, make care of the spine difficult. A thorough understanding of the natural history of these deformities is mandatory for appropriate treatment to be rendered. A team approach that includes physicians from multiple specialties provides the best care for these patients. The two most challenging problems are paralytic scoliosis and rigid lumbar kyphosis. The precise indications for surgical intervention are multifactorial, and the proposed benefits must be weighed against the potential risks. Newer spinal constructs now allow for fixation of the spine in areas previously difficult to instrument. Complications appear to be decreasing with improved understand- ing of the pathophysiology associated with myelomeningocele. S coliosis and kyphosis with sec- ondary adaptive changes are common in the patient with myelo- meningocele. Developmental defor- mities are acquired and are related to the level of paralysis; congenital de- formities result from malforma- tions, such as hemivertebrae. Both forms may exist concurrently. From 1983 to 1990, the preva- lence of neural tube defects (ie, my- elomeningocele) in the United States was 4.6 per 10,000. 1 However, with the increased awareness of the im- portance of folic acid consumption during pregnancy, there has been a decrease of between 72% and 100% in the number of overall new neural tube defects. 1 Nearly every patient with myelomeningocele will de- velop hydrocephalus, and approxi- mately 50% of all patients will have some degree of mental retardation. The clinical experience of the au- thors has shown that most of these patients have motor levels at the lumbosacral or sacral level. As the motor level ascends the spine, the prevalence of scoliosis and associ- ated musculoskeletal anomalies in- creases. Prevalence of Spinal Deformity Multiple studies document the so-called incidence of the various types of spine problems in children with myelomeningocele at different ages. 2-7 Whether these numbers rep- resent an actual incidence or a prev- alence is unknown. Cobb measure- ments also have been used to define developmental scoliosis, the preva- James T. Guille, MD John F. Sarwark, MD Henry H. Sherk, MD S. Jay Kumar, MD Dr. Guille is Orthopaedic Surgeon, Shriners Hospital for Children, Philadelphia, PA. Dr. Sarwark is Chairman, Department of Orthopaedic Surgery, The Children’s Memorial Hospital, Chicago, IL, and Professor of Orthopaedic Surgery, Northwestern University Feinberg School of Medicine, Chicago. Dr. Sherk is Professor, Department of Orthopaedic Surgery, Drexel University College of Medicine, Philadelphia. Dr. Kumar is Director, Spinal Dysfunction Clinic, Alfred I. duPont Hospital for Children, Wilmington, DE, and Clinical Professor of Orthopaedic Surgery, Jefferson Medical College of Thomas Jefferson University, Philadelphia. None of the following authors or the departments with which they are affiliated has received anything of value from or owns stock in a commercial company or institution related directly or indirectly to the subject of this article: Dr. Guille, Dr. Sarwark, Dr. Sherk, and Dr. Kumar. Reprint requests: Dr. Guille, Shriners Hospital for Children, 3551 North Broad Street, Philadelphia, PA 19140. J Am Acad Orthop Surg 2006;14:294- 302 Copyright 2006 by the American Academy of Orthopaedic Surgeons. 294 Journal of the American Academy of Orthopaedic Surgeons lence of which ranges from 52% to 89% in this population. The preva- lence of congenital scoliosis ranges from 7% to 20%. More than 80% of patients aged >10 years will have scoliosis. Using rigid criteria, Trive- di et al 2 recently defined develop- mental scoliosis in this patient pop- ulation as a Cobb magnitude >20°. This figure was chosen because curves of less than this magnitude often were observed to improve or even to resolve. The authors con- cluded that when a scoliosis did not develop by age 15 years, the child would not develop a curve later in life. Associated Health Issues The global health concerns in these children are numerous and may dra- matically influence the care of the spinal deformity. Common issues include central nervous system in- volvement, such as mental retarda- tion, hydrocephalus requiring shunt- ing, and tethering problems of the brain and spinal cord. Insensate skin, latex allergy, renal anomalies, bacte- rial colonization of the urinary tract, bowel and bladder incontinence, and lower extremity malalignment are other factors that often require eval- uation and treatment. Ongoing care and assessment are most effectively done by a team approach. In addition to the orthopaedic surgeon, mem- bers of the team should include a pe- diatrician, neurosurgeon, urologist, physiatrist, orthotist, physical ther- apist, and social worker. Renal anomalies occur in 4% to 17% of patients with myelomenin- gocele, with a higher association in those with congenital vertebral anomalies. 8 Aplasia or dysgenesis of the kidneys is associated with tho- racic and upper lumbar level defects; anomalies of the ureters, especially duplication, are associated with low- er lumbar and sacral level defects. Secondary changes, such as scarring, may occur in the urinary tract as a result of chronic or recurrent infec- tion. Therefore, renal dysfunction is common and requires routine mon- itoring. Latex allergy occurs in 18% to 40% of patients with myelomenin- gocele and may be life-threatening. 9 The allergy is a type I immunoglob- ulin E (IgE)-mediated response to natural plant antigens in the latex and is not an actual allergy to the la- tex itself. Repeated exposure to latex products (from urinary catheteriza- tions, hospitalizations, or surgical procedures) ultimately may sensi- tize these patients to these antigens. The value of an allergen-specific IgE antibody test in detecting indi- viduals with latex allergy is ques- tionable; therefore, a latex-free pro- tocol should be used for every patient at all times. Musculoskeletal Evaluation A complete history and baseline physical examination by the special- ty team should be done in every child. Serial examinations are rec- ommended every 4 to 6 months to document changes in neurologic and functional status. The extremities are examined for range of motion, muscle strength, and the presence of skin ulcers or breakdown. Truncal and sitting alignment are evaluated, with decompensation and rotational prominences noted. Wheelchair and prosthetic modifications are made as needed in consultation with the ap- propriate skilled vendor and thera- pists. Baseline radiographs should be done of the entire spine in the an- teroposterior and lateral planes, with notation made as to whether the ra- diographs were made in the supine, sitting, or standing position. Except in low lumbar and sacral level pa- tients who can stand independently, radiographs preferably are done in the sitting position. Evidence of deformity, associated congenital anomalies, and the level of the spi- nal dysraphism should be recorded. Serial radiographs should be per- formed every 6 months to document curve stability or progression. A magnetic resonance imaging (MRI) study of the brain and spinal canal should be done within the first 2 years of life for baseline purposes; studies should be repeated when clinically indicated. Myelography is reserved for patients in whom the spinal deformity is sufficiently se- vere to preclude adequate interpreta- tion of MRI scans, in patients with metal implants, and as part of the evaluation of a child with a tethered cord. 10 Anomalies of the central nervous system include hydrocephalus, cere- bellar malformations, hydromyelia, syringomyelia, spinal cord anoma- lies, and tethered cord. After birth but before discharge, >90% of chil- dren with myelomeningocele devel- op hydrocephalus and a Chiari II malformation following spinal/skin closure. Hydromyelia and syringo- myelia have been reported in ap- proximately 50% of patients. 5,10 At- rophy of the spinal cord is seen in 15% of patients, lipomas and der- moids in 11% to 38%, and diastem- atomyelia in 2% to 7%; any of these anomalies may cause neurologic de- terioration. Scoliosis associated with hydromyelia or syringomyelia is typ- ically an S-shaped curve in the tho- racic or thoracolumbar region. No good guidelines exist as to when and how a syringomyelia becomes symp- tomatic and when it should be drained; evaluation of a syringomy- elia requires the consultation of a neurosurgeon. MRI is a mainstay in detecting and monitoring these con- ditions. Signs of a tethered cord in the pa- tient with myelomeningocele can include deterioration in gait, increas- ing spasticity, weakness, limb defor- mities, back pain, changes in conti- nence, and rapid increase in the curve magnitude of scoliosis. 11,12 The curve, when present, is usually in the thoracolumbar or lumbar re- James T. Guille, MD, et al Volume 14, Number 5, May 2006 295 gion and is associated with increased lumbar lordosis. Some authors now think that the signs of a tethered spi- nal cord are a result of pressure on the cord from repeated flexion and extension of the spine at the site causing focal flattening, rather than from an actual tethering effect on the ascent of the spinal cord. 11 Sar- wark et al 12 found that in a select group of children with L3 motor lev- el or lower and no hydromyelia, re- lease of a tethered cord resulted in a 58% chance of stabilization or im- provement of curve magnitude. Equivocal results also were seen in patients with spasticity. Pierz et al 11 found no improvement in curve magnitude following detethering in patients who presented with thorac- ic neurologic levels or a curve >40°. Developmental Scoliosis Frequently seen in young children, developmental scoliosis primarily re- sulting from paralysis typically is a long, sweeping, C-shaped curve with or without pelvic obliquity. The con- vexity of the curve often is opposite the side of the elevated pelvis. A dis- location of the hip alone does not ap- pear to be the cause of the scoliosis; the curve develops from muscle im- balance secondary to paralysis and is commonly associated with kyphosis, not lordosis. Often upper extremity function is diverted because the hands are used to support the trunk. Many factors correlate with the occurrence of developmental scolio- sis. Clinical motor level is an impor- tant predictor. 2,6 Trivedi et al 2 found the prevalence of scoliosis to be 93%, 72%, 43%, and <1%, respec- tively, in patients with thoracic, up- per lumbar , lower lumbar, and sacral motor levels. The level of the last in- tact laminar arch (LILA) is another important predictive factor in the development of scoliosis. 4,7 Trivedi et al 2 found the prevalence of scolio- sis to be 89%, 44%, 12%, and 0%, respectively, in patients with thorac- ic, upper lumbar, lower lumbar, and sacral LILAs. The LILA is not always synonymous with the motor level. Overall, it appears that the three most important factors in predicting the development of scoliosis are the motor level, ambulatory status, and LILA. To a lesser degree, hip dislocation/subluxation and lower extremity spasticity also are predic- tive factors. Muller et al 13 studied the progres- sion of scoliosis in 64 patients. The fastest progression was seen during the early teenage years, although it may occur earlier; the scoliosis typ- ically stopped with the cessation of growth. Progression was found to be related to the size of the curve: curves <20° progressed slowly, whereas those >40° progressed more quickly (approximately 13° per year). Nonambulatory patients had a great- er progression rate; however, no cor- relation was made between the lev- el of spinal defect and progression. The authors concluded that all curves should be observed closely and treated before a magnitude of 40° is reached. Marchesi et al 14 also found that scoliosis is a progres- sive condition, especially in young- er children, and that there was less chance for progression when the curve was detected after age 10 years. In a child with a scoliosis <20°, observation with radiographs every 4 to 6 months is suggested. When the curve is >20°, use of a brace should be considered. Because the role of bracing in these patients is controversial, its use is left to the choice of the surgeon and his or her experience. Although most agree that bracing does not stop curve pro- gression or completely eliminate the need for spinal fusion, bracing may slow the progression of a curve and allow for further trunk growth be- fore eventual spinal fusion. Muller and Nordwall 15 reported on the use of the Boston brace in the management of scoliosis and found that when treatment was instituted early and before the curve reached 45°, the brace could arrest progres- sion of the cur ve. These results, however, have not been reported by others. The brace we have recom- mended is custom-molded and does not interfere with pulmonary function, lower extremity bracing, self-catheterization, or sitting—a challenge in some patients. Obesity may be a relative contraindication. The brace aids in sitting balance and frees the hands for function. Patients who use a brace need to have their skin checked daily for areas of pres- sure and breakdown, although a custom-fitted brace usually avoids these problems. Surgical Indications and Principles Listing the absolute indications for surgical intervention is difficult because the long-term natural histo- ry of untreated spinal deformity in this population is relatively un- known. Most agree, however, that progressive scoliosis >50° that caus- es sitting imbalance is an important indication. McMaster 16 thought that loss of function as an indication was more important than the degree of curvature. Ideally, spinal reconstruc- tion would be done after most adult sitting height is attained; however, the surgeon is infrequently afforded this optimal scenario. Because it is common for sur- geons to want to procrastinate in treating these curves surgically, a di- lemma arises when a younger child presents with a large progressive curve and sitting imbalance. The ideal solution to this problem has yet to be found. The use of a growing rod system in these patients has been reported. Medical comorbidi- ties, such as shunt function, pulmo- nary function, skin condition, and urinary tract infection, require eval- uation and treatment before surgery. When poor tissue coverage is a con- cern, consultation with a plastic sur- geon is advised to consider the use of preoperative tissue expanders. Congenital and Developmental Deformities of the Spine in Children With Myelomeningocele 296 Journal of the American Academy of Orthopaedic Surgeons Combined anterior and posterior arthrodesis and instrumentation provide the best chance to achieve a durable fusion. 16-20 Anterior diskec- tomy improves the preinstrumenta- tion flexibility and correctability of the curve, and anterior interbody fu- sion increases the strength of the en- tire fusion mass. The addition of al- lograft bone may be necessary in patients who have had prior bone graft harvesting, in those with small ilia, and in those requiring long fu- sions. Bone graft substitutes and growth factors may play an impor- tant role in the future. Anterior fusion and instrumenta- tion alone is again being considered for selected curves. Sponseller et al 21 revisited this technique and had good results with anterior fusion alone only when the thoracolumbar curve was <75°; when there were no syrinx, no increased kyphosis, and no compensatory curve >40°; and when there was independent sitting balance. Parsch et al 19 recommended instrumented anterior and posterior fusions, especially in patients with thoracic level paralysis, to decrease the rate of implantation failure and to prevent postoperative loss of cor- rection. In the series of Stella et al, 22 the best corrections were obtained in patients who had instrumented an- terior and posterior fusions. The fusion should extend from the upper thoracic vertebrae to the sacrum in nonambulators and should include all curves. Careful consideration should be given to the type of posterior incision and surgi- cal approach. Although either a transverse or triradiate incision of- fers better exposure laterally, the triradiate incision is associated with a 40% rate of skin necrosis; 18 there- fore, a single longitudinal straight in- cision generally is preferred. Wide flaps should be developed laterally to aid in wound closure. Instrumentation without spinal fusion is not recommended in this patient population; neither is fusion without instrumentation, except for congenital anomalies requiring in situ fusions. Segmental posterior in- strumentation provides a means of curve correction and all but elimi- nates postoperative immobilization. Posterior spinal fusion with instru- mentation alone has unacceptably high rates of failure. 20,23 Instrumen- tation of the dysraphic spine is diffi- cult, and the surgeon must use skill and experience in determining surgical strategies and in choosing the vertebral elements to the im- plant. When laminae are present, sublaminar wires or cables are passed in the standard caudocepha- lad fashion; when laminae are ab- sent, drill holes may be made in the vertebral bodies for anchor sites. Pedicle screw fixation offers many solutions; in this population, how- ever, the pedicles often are small, dysplastic, and maloriented. Rodgers et al 24 have shown that pedicle screw instrumentation allowed preserva- tion and correction of lumbar lordo- sis and that the anterior approach possibly could be avoided. This tech- nique also may allow the surgeon to end the fusion above the sacrum, which may be beneficial in select ambulatory patients. Multihook sys- tems are effective in the thoracic spine in which the anatomy is more nearly normal. Consideration should be given to the use of titanium im- plants if MRI studies of the region will be needed later. Sacral and pel- vic fixation generally is thought to be mandatory in patients with fixed pel- vic obliquity. However, Wild et al 25 reported spontaneous correction of the pelvic obliquity following ante- rior and posterior spinal fusion. Use of the Galveston technique may be challenging secondary to small, dysplastic, osteoporotic ilia. The Dunn-McCarthy or Warner- Fackler techniques of sacral fixation may be preferred in these pa- tients. 26-29 Postoperatively, the pa- tient should be mobilized as soon as possible. When stable, rigid fixation is achieved, postoperative immobi- lization with a cast or brace is op- tional and left to the surgeon’s dis- cretion. Prolonged postoperative immobilization is associated with skin problems as well as fractures from disuse osteoporosis. Complications Spinal surgery in this challenging patient population is associated with higher rates of complication. 18,23 Wound infection may occur in up to half of these patients, as well as inci- sional necrosis (commonly seen when a triradiate incision is used). However, Ward et al 18 found no long- term disability from incisional skin necrosis in their patients. Infection rates have approached 43% and are highest when surgery is performed with concurrent urinary tract infec- tion. 18 Preoperative urinary cultures are mandatory, as is treatment with antibiotics preoperatively and post- operatively. Foley catheters should be re- moved as soon as the patient is med- ically stable. Intravenous antibiotics should be continued postoperatively until discharge. The rate of neuro- logic deficit is low but can be perma- nent. 18,30 Cerebrospinal fluid leaks may occur as a result of the surgical dissection or tethering of the spinal cord. Progression of the curve may occur above and below the fusion mass when selection of the fus- ion levels is inappropriately short. Pseudarthrosis occurs in up to 76% of patients and is related to the sur- gical approach, type and presence of instrumentation, or use of a posteri- or approach alone. 20,22 The pseudar- throsis rate is 0% to 50% with an isolated anterior arthrodesis, 26% to 76% with an isolated posterior ar- throdesis, and 5% to 23% with a combined anterior and posterior ar- throdesis (Figure 1). Pseudarthrosis secondary to implant failure has oc- curred in up to 65% of cases. 16,18,30 Fractures of the extremities second- ary to disuse osteoporosis from im- mobilization are common. Shunt malfunction may occur following acute correction of large curves. 23 James T. Guille, MD, et al Volume 14, Number 5, May 2006 297 In more than half of patients in some series, reduced walking ability in preoperative ambulators af- ter surgery has been reported. 30,31 There may occasionally be an im- provement in activities of daily liv- ing (eg, sitting balance), but hip flex- ion contractures may increase. A greater potential for ambulation ex- ists when the scoliosis is <40° and pelvic obliquity is <25°. The eval- uation of postoperative patient activ- ity (and function) is multifactorial and can be affected by older age, obe- sity, neurologic level, central axis le- sions, and motivation of the patient. Improved pulmonary function has been reported after anterior and pos- terior spine fusion procedures. 32 Pa- tients may have problems with self- catheterization after spinal surgery; however, i n these situations, modal- ities such as mirrors with central holes can be used by the patient. As an alternative, urologic bladder di- version procedures may be per- formed. Skin sores may develop when changes in sitting balance re- distribute pressure on the skin. Congenital Scoliosis Congenital scoliosis in the patient with myelomeningocele should be treated using the same principles as those used in otherwise normal chil- dren. The natural history of this anomaly is similar in children both with and without a myelomeningo- cele. In both clinical settings, a strong association between the pres- ence of congenitally dysplastic ver- tebrae and renal anomalies exists. Rigid Lumbar and Thoracolumbar Kyphosis Banta and Hamada 33 found that 46 of 457 patients had developmental ky- phosis, rigid congenital kyphosis, or kyphoscoliosis that progressed an average of 8°, 8.3°, and 6.8° per year, respectively. 34 The prevalence of rig- id kyphosis of the lumbar spine rang- es from 8% to 15%, depending on the series. 35-38 The curve may be ini- tially large at birth, and progression can range from 4° to 12° per year. 39 Mintz et al 35 reviewed 51 children who had a rigid kyphosis at birth; 40 of these patients had a thoracic level paralysis, and 9 of the remain- ing 11 patients had grade 3 motor strength in the quadriceps. Progres- sion becomes more rapid after the first year of life, when the child be- gins to sit. The fixed compensatory thoracic lordosis, so commonly seen in older patients, is not present at birth and progresses by approximate- ly 2.5° per year. 36 Children with rigid lumbar ky- phosis have a characteristic clinical appearance: they sit on the posterior aspect of the sacrum with a protu- berant abdomen and kyphotic gib- bus. Occasionally, an extension de- formity of the cervical spine may develop to balance the trunk. The legs appear to be long because of the flexed position of the pelvis, and the lower ribs are splayed later- ally. These children usually are more severely neurologically in- volved, have a higher prevalence of hydrocephalus, and have a poorer quality of life. Thoracolumbar ky- phosis is characterized by a collaps- ing C-shaped curve with its apex found in the lower thoracic or lum- bar region; it is supple early but can become rigid. Figure 1 Postoperative images of a patient with myelomeningocele scoliosis. A, Anteropos- terior radiograph following anterior fusion with placement of interbody cages and posterior fusion/instrumentation to the sacropelvis. Note restoration of coronal bal- ance. B, Lateral radiograph demonstrating restoration of sagittal balance. Congenital and Developmental Deformities of the Spine in Children With Myelomeningocele 298 Journal of the American Academy of Orthopaedic Surgeons Atrophic or absent erector spinae muscles allow the quadratus lumbo- rum muscle to become a flexor of the spine. 37 The erector spinae mus- cles, when present and functioning, act as flexors of the spine in their po- sition anterior to the pedicles. Hy- pertrophic psoas muscles also may act as flexors of the spine, along with the crura of the diaphragm. The dys- plastic laminae and pedicles are di- rected laterally, and the interverte- bral articulations are absent or rudimentary. With the development of sitting, the increased moment arm and physiologic load lead to a progressive kyphotic deformity, which continues until the vertebral bodies become wedge-shaped ante- riorly and the rib cage rests on the pelvis. The rationale for surgical treat- ment of rigid lumbar kyphosis is based on many functional factors, but the absolute criteria remain ill- defined. The defor mity is progres- sive in all cases and is recalcitrant to nonsurgical treatment. The abnor- mal sitting posture often forces the child to rely on the hands for sup- port, thus diverting their use from functional activities. Repeated epi- sodes of skin breakdown occurring over the apex of the kyphosis are dif- ficult to prevent and create risk for the patient. These two clinical sce- narios—abnormal sitting and skin breakdown—are perhaps the most compelling reasons for surgical in- tervention. Compression of the ab- dominal contents from the kyphotic deformity also has been suggested as a theoretic concern, yet no study has documented functional benefits re- lated to this parameter following kyphectomy. Families often worry about shortened trunk height; how- ever, performing multilevel corpec- tomies and osteotomies may exacer- bate this problem. Respiratory compromise in untreated deformity also is a concern. However, most of these patients have low aerobic de- mand, and adaptive changes (eg, flared ribs, barrel-shaped chests) may partially compensate. Mar tin et al 38 showed that, with wheelchair mod- ifications, these children can do well and may complain only of the cos- metic deformity. The most appropriate timing and the optimal type of surgery are areas of controversy. Bracing can be used early to slow the progression of de- formity, but a surgical intervention is nearly always required. As the child ages, the deformity becomes more rigid, and a compensatory fixed thoracic lordosis develops. Initial at- tempts at correction involve resec- tion or osteotomy of the apical ver- tebrae, with little attention directed to the proximal thoracic lordosis. Proponents of neonatal kyphectomy at the time of closure of the my- elomeningocele report that the pro- cedure is safe and provides good initial correction. 40 Even though re- currence of the kyphosis was com- mon, the new deformity was less rig- id and easier to address. 40 More extensive fusion and instrumenta- tion are required in the older child, and complication rates are higher. 41 These children also require an ex- tensive preoperative evaluation. An area of interest has been determining the course of the abdominal aorta 42 as well as the method of most effec- tive evaluation (ie, aortography, MRI, ultrasound, computed tomog- raphy). All published studies noted here have shown that the abdominal aorta does not follow the path of the kyphosis and is at little risk during kyphectomy. Preoperative shunt function should be tested. When cor- dotomy is to be performed, the pro- cedure should not be done at the same level of the dura. This will al- low the cerebrospinal fluid to circu- late and avoids an increase in intra- cranial pressure. Lalonde and Jarvis 43 showed that cordotomy al- lows for better correction, potential- ly decreasing spasticity and poten- tially positively affecting bladder function. However, undertaking a cordotomy increases surgical time and the degree of blood loss. For thoracolumbar kyphosis, Lindseth and Stelzer 39 described re- moval of the cancellous bone from the vertebra above and the one be- low the apical ver tebra, which can be performed at any age. The poste- rior elements are removed, and an eggshell-type procedure is performed without violating the end plates. The apical vertebra is then pushed forward, thus correcting the kypho- sis. Fusion is done posteriorly only so that continued anterior growth may provide further correction of the kyphosis. Fixation is with tension-band wiring around the pedicles in younger children and with sublaminar wires, pedicle screws, and rods in older children. For rigid lumbar kyphosis, the pro- cedures include kyphectomy as de- scribed by Lindseth and Stelzer. 39 This entails resection or osteotomy of the proximal portion of the apical vertebra of the gibbus and of the dis- tal segments of the adjacent lordosis, with limited fusion and wire fixa- tion. 44 In 39 patients (average follow- up, 11.1 years), Lintner and Lind- seth 44 reported that 34 had a partial loss of cor rection, but only 2 patients settled into a position worse than their preoperative deformity. The three remaining patients maintained their correction. In the younger child, the kyphectomy is followed by a lim- ited fusion to preserve growth of the adjacent vertebrae. In the older child, kyphectomy should be accompanied by more extensive fusion and instru- mentation to the pelvis or sacrum (Figure 2). The optimal instrumenta- tion and distal fixation technique have yet to be determined. 45-48 Sarwark 49 reported on the sub- traction osteotomy of multiple ver- tebral bodies at the apex, which cre- ates lordosing osteotomies at each level. 50 The vertebral body can be entered and subtracted via the pedi- cles with a curette, distal to proxi- mal. A closing osteotomy is then done posteriorly to obtain correc- tion. This procedure is done in chil- dren younger than age 5 years and is James T. Guille, MD, et al Volume 14, Number 5, May 2006 299 supplemented with full sagittal in- strumentation from the midtho- racic level to the sacrum. Excellent correction and restoration of the sagittal alignment can be obtained, but long-term results after comple- tion of growth are needed to observe all related losses of correction (Fig- ure 3). Reported advantages include less blood loss, decreased morbidity, no need for cordotomy, and contin- ued growth because the end plates are not violated. Summary Care of the child with myelomenin- gocele who has a spinal deformity, such as paralytic scoliosis or rigid lumbar kyphosis, is challenging be- cause of the presence of medical co- morbidities, such as central nervous system involvement, renal anoma- lies, and potential latex allergy. Eval- uation and management of these children requires a team approach with physicians from multiple spe- cialties. Preoperative discussions with the patient and family must ad- dress their perceived as well as the actual benefits of treatment. 51 Early treatment, which may include com- bined anterior and posterior arthro- Figure 2 Rigid lumbar kyphosis in a 13-year-old boy. A, Preoperative lateral radiograph showing a 119° curve. B, Antero- posterior radiograph showing minimal deformity in the coronal plane. C, Clinical photograph of the deformity. Eighteen months postoperatively, there is excellent correction in the antero- posterior (D) and lateral (E) planes following resection of the first and second lumbar vertebrae and instrumentation with Dunn-McCarthy rods. (Case courtesy of B. Stephens Richards, MD, Dallas, TX.) Congenital and Developmental Deformities of the Spine in Children With Myelomeningocele 300 Journal of the American Academy of Orthopaedic Surgeons desis and instrumentation, anterior diskectomy, anterior interbody fu- sion, or the addition of allograft bone, is required to avoid the pro- gression of curves to severe deformi- ty that later may require extensive measures. Besides using skill and ex- perience during surgical procedures of the spine, the surgeon must be fa- miliar with and be prepared to use different kinds of implants. Al- though the surgical treatment of these patients remains difficult and is associated with higher complica- tion rates, new implant designs, careful attention to detail, and pre- operative planning can yield suc- cessful results with minimal associ- ated problems and complications. References Citation numbers printed in bold type indicate references published within the past 5 years. 1. 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Sarwark JF: Kyphosis deformity in myelomeningocele. Orthop Clin North Am 1999;30:451-455. 50. Nolden MT, Sarwark JF, Vora A, Gray- hack JJ: A kyphectomy technique with reduced perioperative morbidity for myelomeningocele kyphosis. Spine 2002;27:1807-1813. 51. Wai EK, Young NL, Feldman BM, Bad- ley EM, Wright JG: The relationship between function, self-perception, and spinal deformity: Implications for treatment of scoliosis in children with spina bifida. J Pediatr Or thop 2005;25:64-68. Congenital and Developmental Deformities of the Spine in Children With Myelomeningocele 302 Journal of the American Academy of Orthopaedic Surgeons . deformity. Common issues include central nervous system in- volvement, such as mental retarda- tion, hydrocephalus requiring shunt- ing, and tethering problems of the brain and spinal cord. Insensate. di- lemma arises when a younger child presents with a large progressive curve and sitting imbalance. The ideal solution to this problem has yet to be found. The use of a growing rod system in. medical co- morbidities, such as central nervous system involvement, renal anoma- lies, and potential latex allergy. Eval- uation and management of these children requires a team approach with